From 5c975b8725cf9d8b754272ab12ee7deedec0a2b7 Mon Sep 17 00:00:00 2001
From: iou1name <iou1name@national.shitposting.agency>
Date: Mon, 11 May 2020 12:41:26 -0400
Subject: [PATCH] web audio attempt

---
 scorch.py            | 43 +++++++++++++++++++++++++-
 static/scorch.js     | 73 ++++++++++++++++++++++++++++++++++++++++++++
 templates/index.html |  4 +++
 3 files changed, 119 insertions(+), 1 deletion(-)

diff --git a/scorch.py b/scorch.py
index 38ec95b..9a78fe1 100644
--- a/scorch.py
+++ b/scorch.py
@@ -2,7 +2,9 @@
 """
 A music streaming application.
 """
-from aiohttp import web
+import asyncio
+
+from aiohttp import web, WSMsgType
 import jinja2
 import aiohttp_jinja2
 from aiohttp_jinja2 import render_template
@@ -14,12 +16,51 @@ import buckler_aiohttp
 uvloop.install()
 routes = web.RouteTableDef()
 
+with open ('test.opus', 'rb') as file:
+	test_data = file.read()
+
+def chunker(seq, size):
+	return (seq[pos:pos + size] for pos in range(0, len(seq), size))
+
+async def send_files(ws):
+	for n, chunk in enumerate(chunker(test_data, 200*1024)):
+		print(f"sending packet #{n}")
+		await ws.send_bytes(chunk)
+		await asyncio.sleep(5)
+	
+
 @routes.get('/', name='index')
 async def index(request):
 	"""The index page."""
 	return render_template('index.html', request, {})
 
 
+@routes.get('/ws', name='ws')
+async def websocket_handler(request):
+	"""The websocket endpoint."""
+	ws = web.WebSocketResponse(heartbeat=30)
+	ws_ready = ws.can_prepare(request)
+	if not ws_ready.ok:
+		return web.Response(text="Cannot start websocket.")
+	await ws.prepare(request)
+
+	async for msg in ws:
+		if msg.type != WSMsgType.TEXT:
+			break
+
+		if msg.data == "ping":
+			print('ping')
+			await ws.send_str("pong")
+
+		if msg.data == 'test':
+			print('initiating test')
+			asyncio.create_task(send_files(ws))
+
+
+	await ws.close()
+	return ws
+
+
 async def init_app():
 	"""Initializes the application."""
 	app = web.Application(middlewares=[buckler_aiohttp.buckler_session])
diff --git a/static/scorch.js b/static/scorch.js
index e69de29..ec33c4e 100644
--- a/static/scorch.js
+++ b/static/scorch.js
@@ -0,0 +1,73 @@
+var socket;
+var audioCtx = new window.AudioContext();
+var source = audioCtx.createBufferSource();
+var total_raw;
+
+function appendBuffer(buffer1, buffer2) {
+	let numberOfChannels = Math.min( buffer1.numberOfChannels, buffer2.numberOfChannels );
+	let tmp = audioCtx.createBuffer( numberOfChannels, (buffer1.length + buffer2.length), buffer1.sampleRate );
+	for (let i=0; i<numberOfChannels; i++) {
+		let channel = tmp.getChannelData(i);
+		channel.set( buffer1.getChannelData(i), 0);
+		channel.set( buffer2.getChannelData(i), buffer1.length);
+	}
+	return tmp;
+}
+
+function appendBuffer2(buffer1, buffer2) {
+	var tmp = new Uint8Array(buffer1.byteLength + buffer2.byteLength);
+	var buff1 = new Uint8Array(buffer1);
+	var buff2 = new Uint8Array(buffer2);
+	tmp.set(buff1, 0);
+	tmp.set(buff2, buffer1.byteLength);
+	return tmp.buffer;
+};
+
+function load() {
+	socket = init_websocket();
+}
+
+/* Websocket setup */
+function init_websocket() {
+	let socket = new WebSocket('wss://' + window.location.hostname + ws_uri);
+	socket.binaryType = "arraybuffer";
+	socket.onmessage = onmessage;
+	socket.onclose = onclose;
+	socket.onerror = onerror;
+	socket.events = {};
+	return socket;
+}
+
+function onmessage (e) {
+	console.log(e);
+	if (e.data.constructor === ArrayBuffer) {
+		console.log(e.data.byteLength);
+		if (source.buffer != null) {
+			total_raw = appendBuffer2(total_raw, e.data);
+		} else {
+			total_raw = e.data;
+		}
+		audioCtx.decodeAudioData(total_raw.slice(0)).then(function(decodedBuffer) {
+			if (source.buffer != null) {
+				source.stop();
+			}
+			source = audioCtx.createBufferSource();
+			source.buffer = decodedBuffer;
+			source.connect(audioCtx.destination);
+			source.start(0, audioCtx.currentTime);
+		});
+	}
+}
+
+function onclose(e) {
+	if (e.wasClean) { return; } // no need to reconnect
+	console.log(e);
+	console.log('Websocket lost connection to server. Re-trying...');
+	//socket = init_websocket();
+	//await sleep(5000);
+}
+
+function onerror(e) {
+	console.log("Websocket error!")
+	console.log(e);
+}
diff --git a/templates/index.html b/templates/index.html
index 90bdff8..bcda2f8 100644
--- a/templates/index.html
+++ b/templates/index.html
@@ -3,7 +3,9 @@
 	<head>
 		<title>Scorch</title>
 		<link rel="stylesheet" type="text/css" href="/static/scorch.css">
+		<script>const ws_uri = "{{ url('ws') }}";</script>
 		<script type="text/javascript" src="/static/scorch.js"></script>
+		<script>window.onload = load;</script>
 		<meta name="viewport" content="width=device-width, initial-scale=0.8">
 		<meta name="description" content="A music streaming service.">
 	</head>
@@ -12,6 +14,8 @@
 			<h1>Scorch</h1>
 		</header>
 		<main>
+			<button onclick="socket.send('test')">Test</button>
+			<audio controls></audio>
 		</main>
 	</body>
 </html>